Ultra-dense photonic integration of e-skid waveguides enabled by van der Waals materials
D.V. Grudinin'*, G.A. Ermolaev2, R.V. Kirtaev2, A.S. Slavich1, A.A. Vyshnevyy1, K.V. Voronin1, A.V. Arsenin1, V.S. Volkov2
1- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, 9 Institutskiy Lane,
Dolgoprudny, 141701, Moscow Region, Russia
2- Emerging Technologies Research Center, XPANCEO, Dubai Investment Park First, Dubai, United Arab
Emirates
* grudinin. dv@phystech. edu
Photonics represents the natural technological progression following the era of electronics. However, the diffraction limit of light and crosstalk present significant challenges for photonic elements, constraining their size and integration density. In this study, we demonstrate that layered semiconductors can overcome these challenges due to their pronounced optical anisotropy. Specifically, we explore silicon waveguides using hexagonal boron nitride (hBN), molybdenum disulfide (MoS2), and tungsten disulfide (WS2) as top and bottom claddings. These waveguides operate at a telecommunications wavelength of 1550 nm, just above the diffraction limit (by approximately 5%), and exhibit exceptional coupling between vertically stacked waveguides. This allows for the possibility of multiple layers of independent integrated components. We visualize these waveguides experimentally using near-field optical microscopy and provide extensive theoretical analysis of the effective mode area and coupling length of the waveguides. Our results pave the way for ultra-dense photonic integration based on layered materials.
We gratefully acknowledge the financial support from the Russian Science Foundation (grant No. 22-19-00738).